This invention relates to intraocular lenses suitable for use as artificial lens implants.
There are many known structural arrangements for intraocular lenses. Some of these are disclosed in the following U.S. Patents. To the extent that these Patents disclose techniques of manufacture, materials and use, they are incorporated herein by reference:
U.S. Pat. No. 4,363,143--Callahan (1982); PA0 U.S. Pat. No. 4,270,230--Poler (1981); PA0 U.S. Pat. No. 4,249,271--Poler (1981); PA0 U.S. Pat. No. 4,244,060--Hoffer (1981); PA0 U.S. Pat. No. 4,174,543--Kelman (1979); PA0 U.S. Pat. No. 4,092,743--Kelman (1978); PA0 U.S. Pat. No. 4,159,546--Shearing (1979); PA0 U.S. Pat. No. 4,014,049--Richards, et al. (1977); PA0 U.S. Pat. No. 4,073,014--Poler (1978); PA0 U.S. Pat. No. 3,975,779--Richards, et al. (1976); PA0 U.S. Pat. No. 3,913,148--Potthast (1975); PA0 U.S. Pat. No. 3,906,551--Otter (1975); PA0 U.S. Pat. No. 3,866,249--Flom (1975); PA0 U.S. Pat. No. 3,673,616--Federov, et al. (1972);
Despite these many known lens designs, the "ideal" artificial lens implant has still not been found. Perhaps the large number of such designs is suggestive of the fact that the problem is still unsolved. Ideally, an artificial lens implant would be universal, i.e., one lens design would be suitable for implantation into any human eye. Accommodation for size and orientation would be made for posterior or capsular sac placements over anterior placement; and, of course, the focal length would have to be properly selected; but the basic lens design would be unchanged. Using such a universal design, a surgeon would not have to stock all common permutations of size and design in anticipation of those situations wherein all necessary information for selecting the proper lens is available only after surgically opening the eye. That is, the ideal lens design would be capable of being fitted in the anterior or posterior chambers, or in the capsular sac, at the surgeon's discretion, or by reasons revealed during surgery. Secondly, the ideal artificial lens would exhibit a high degree of positional stability within the eye. That is, it would not be displaced by everyday vibrations and shocks to the eye, or by violent trauma. Thirdly, the ideal lens would be relatively easy and safe to insert and withdraw from the eye. Fourthly, regardless of the size of the eye into which the artificial lens is inserted, the ideal lens would exert a relative constant force against the eye tissue and that force would be predictable. This concept of constant, evenly distributed force should also act to inhibit the ideal lens from vaulting anteriorly.
The lenses disclosed by the prior U.S. patents, listed above, do not meet all of these criteria.